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<h1 class="refname">MongoCollection::deleteIndex</h1>
<p class="verinfo">(PECL mongo >=0.9.0)</p><p class="refpurpose"><span class="refname">MongoCollection::deleteIndex</span> — <span class="dc-title">Deletes an index from this collection</span></p>
</div>
<div class="refsect1 description" id="refsect1-mongocollection.deleteindex-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="modifier">public</span> <span class="type">array</span> <span class="methodname"><strong>MongoCollection::deleteIndex</strong></span>
( <span class="methodparam"><span class="type"><span class="type string|array">string|array</span></span> <code class="parameter">$keys</code></span>
)</div>
<p class="para rdfs-comment">
This method is identical to:
</p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /><br /></span><span style="color: #007700">public function </span><span style="color: #0000BB">deleteIndexes</span><span style="color: #007700">(</span><span style="color: #0000BB">$keys</span><span style="color: #007700">) {<br /> </span><span style="color: #0000BB">$indexName </span><span style="color: #007700">= </span><span style="color: #0000BB">$this</span><span style="color: #007700">-></span><span style="color: #0000BB">toIndexString</span><span style="color: #007700">(</span><span style="color: #0000BB">$keys</span><span style="color: #007700">);<br /><br /> return </span><span style="color: #0000BB">$this</span><span style="color: #007700">-></span><span style="color: #0000BB">db</span><span style="color: #007700">-></span><span style="color: #0000BB">command</span><span style="color: #007700">(array(<br /> </span><span style="color: #DD0000">"deleteIndexes" </span><span style="color: #007700">=> </span><span style="color: #0000BB">$this</span><span style="color: #007700">-></span><span style="color: #0000BB">getName</span><span style="color: #007700">(),<br /> </span><span style="color: #DD0000">"index" </span><span style="color: #007700">=> </span><span style="color: #0000BB">$indexName</span><span style="color: #007700">,<br /> ));<br />}<br /><br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
<p class="para">
Each index is given a unique name when it is created. This is often generated
by the driver based on the index key(s) and order/type, but custom names may
also be specified with <span class="function"><a href="mongocollection.createindex.html" class="function">MongoCollection::createIndex()</a></span>'s
<em>"name"</em> option).
</p>
<p class="para">
Unfortunately, <span class="function"><strong>MongoCollection::deleteIndex()</strong></span> cannot
delete custom-named indexes due to a backwards compatibility issue. When a
string argument is provided, it is assumed to be the single field name in an
ascending index (e.g. the name <em>"x_1"</em> would be used for the
argument <em>"x"</em>). If an array or object is provided, an index
name is generated just as if that argument was passed to
<span class="function"><a href="mongocollection.createindex.html" class="function">MongoCollection::createIndex()</a></span>.
</p>
<p class="para">
In order to delete a custom-named index with the PHP driver, the
<em>deleteIndexes</em> database command must be used. For instance,
an index named "myIndex" could be deleted with the PHP driver by running:
</p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /><br />$db</span><span style="color: #007700">-></span><span style="color: #0000BB">command</span><span style="color: #007700">(array(<br /> </span><span style="color: #DD0000">"deleteIndexes" </span><span style="color: #007700">=> </span><span style="color: #0000BB">$collection</span><span style="color: #007700">-></span><span style="color: #0000BB">getName</span><span style="color: #007700">(),<br /> </span><span style="color: #DD0000">"index" </span><span style="color: #007700">=> </span><span style="color: #DD0000">"myIndex"</span><span style="color: #007700">,<br />));<br /><br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
<p class="para">
To determine the name of an index with the PHP driver, you can query the
<em>system.indexes</em> collection of a database and look for the
<em>"name"</em> field of each result. The <em>"ns"</em>
field will indicate the collection to which each index belongs.
</p>
</div>
<div class="refsect1 parameters" id="refsect1-mongocollection.deleteindex-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<code class="parameter">keys</code>
</dt>
<dd>
<p class="para">
An array specifying the index's fields as its keys. For each field, the
value is either the index direction or
<a href="https://docs.mongodb.com/manual/core/index-types/" class="link external">» index type</a>.
If specifying direction, specify <em>1</em> for ascending or
<em>-1</em> for descending.
</p>
<p class="para">
If a string is provided, it is assumed to be the single field name in an
ascending index.
</p>
</dd>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-mongocollection.deleteindex-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
Returns the database response.
</p>
</div>
<div class="refsect1 examples" id="refsect1-mongocollection.deleteindex-examples">
<h3 class="title">Examples</h3>
<div class="example" id="example-1576">
<p><strong>Example #1 <span class="function"><strong>MongoCollection::deleteIndex()</strong></span> example</strong></p>
<div class="example-contents"><p>
This example passes the function string and array parameters.
</p></div>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /><br />$m </span><span style="color: #007700">= new </span><span style="color: #0000BB">MongoClient</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">$c </span><span style="color: #007700">= </span><span style="color: #0000BB">$m</span><span style="color: #007700">-></span><span style="color: #0000BB">example</span><span style="color: #007700">-></span><span style="color: #0000BB">indices</span><span style="color: #007700">;<br /><br /></span><span style="color: #FF8000">// create and remove a simple index<br /></span><span style="color: #0000BB">$c</span><span style="color: #007700">-></span><span style="color: #0000BB">createIndex</span><span style="color: #007700">(array(</span><span style="color: #DD0000">"i"</span><span style="color: #007700">=></span><span style="color: #0000BB">1</span><span style="color: #007700">));<br /></span><span style="color: #0000BB">$c</span><span style="color: #007700">-></span><span style="color: #0000BB">deleteIndex</span><span style="color: #007700">(</span><span style="color: #DD0000">"i"</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// create and remove a multi-key index<br /></span><span style="color: #0000BB">$c</span><span style="color: #007700">-></span><span style="color: #0000BB">ensureIndex</span><span style="color: #007700">(array(</span><span style="color: #DD0000">"j" </span><span style="color: #007700">=> </span><span style="color: #0000BB">1</span><span style="color: #007700">, </span><span style="color: #DD0000">"k" </span><span style="color: #007700">=> </span><span style="color: #0000BB">1</span><span style="color: #007700">));<br /></span><span style="color: #0000BB">$c</span><span style="color: #007700">-></span><span style="color: #0000BB">deleteIndex</span><span style="color: #007700">(array(</span><span style="color: #DD0000">"j" </span><span style="color: #007700">=> </span><span style="color: #0000BB">1</span><span style="color: #007700">, </span><span style="color: #DD0000">"k" </span><span style="color: #007700">=> </span><span style="color: #0000BB">1</span><span style="color: #007700">));<br /><br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
</div>
<div class="refsect1 seealso" id="refsect1-mongocollection.deleteindex-seealso">
<h3 class="title">See Also</h3>
<ul class="simplelist">
<li class="member"><span class="methodname"><a href="mongocollection.createindex.html" class="methodname" rel="rdfs-seeAlso">MongoCollection::createIndex()</a> - Creates an index on the specified field(s) if it does not already exist</span></li>
<li class="member"><span class="methodname"><a href="mongocollection.deleteindexes.html" class="methodname" rel="rdfs-seeAlso">MongoCollection::deleteIndexes()</a> - Delete all indices for this collection</span></li>
<li class="member"><span class="methodname"><a href="mongocollection.toindexstring.html" class="methodname" rel="rdfs-seeAlso">MongoCollection::toIndexString()</a> - Converts keys specifying an index to its identifying string</span></li>
<li class="member">
The MongoDB
<a href="https://docs.mongodb.com/manual/indexes/" class="link external">» index</a> and
<a href="https://docs.mongodb.com/manual/core/index-types/" class="link external">» index type</a>
documentation.
</li>
</ul>
</div>
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